One vertex per element, one color per generator, with an edge from x to x·s.
(2,5)(6,8)(9,10)(11,12)(13,18)(14,16)(15,17)(19,20)(21,23)(22,24)(25,26,30,28)(27,33,35,31)(29,32,37,36)(34,39,40,38)(1,2,4,5)(3,6,7,8)(9,11)(10,15)(12,16)(13,19)(14,17)(18,22)(20,23)(21,24)(25,27)(26,31)(28,33)(29,34)(30,35)(32,38)(36,39)(37,40)(1,3,4,7)(2,6,5,8)(10,16)(11,17)(13,21)(20,22)(26,28)(31,33)(32,36)(38,39)(9,11)(10,12)(13,19)(14,17)(15,16)(18,20)(21,24)(22,23)(25,28,30,26)(27,33,35,31)(29,36,37,32)(34,39,40,38)(9,12)(10,17)(11,16)(13,20)(14,15)(18,24)(19,23)(21,22)(25,27)(26,31)(28,33)(29,34)(30,35)(32,38)(36,39)(37,40) involution — undirected(9,13,14,21)(10,18,16,23)(11,19,17,24)(12,20,15,22)(25,29,30,37)(26,32,28,36)(27,34,35,40)(31,38,33,39)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.